Cardinal Blackadder was appointed by Henry VIII soon after Henry’s accession in 1509 to become Keeper of the Privy Rolls. With the contemporaneous appointments of Cardinal Wolsey as Lord Chancellor, and Cardinal Sprunt as Lord Scrivener, this is said to have left Henry free to pursue other activities.

He was a good friend of the King and spent much time with him at Hampton Court. Despite this, there is conjecture that the Cardinal murdered Henry VIII by strangling him with an eel after being caught helping himself to a couple of peerages from the king’s bureau. It is likely that these peerages were those of Lord Blackadder and potentially Lord Whiteadder. The murder was dramatic irony, the Cardinal’s father having been killed by Henry’s father.

It seems the Cardinal was exiled during the reign of Henry’s son, perhaps due to suspicions of his involvement in Henry VIII’s demise. He stayed in a French hideaway and attempted to win favour with an assortment of elaborate sweets which were ignored.

It is known that Lord Edmund Blackadder was prominent during Elizabeth’s reign. It appears that Cardinal Blackadder and his son Lord Blackadder may have been alive at the beginning of her reign because they had kept a "low profile while Mary I was around", suggesting that they outlasted her. However, this is not clear and certainly Lord Edmund Blackadder II’s father had died prior to the events in Blackadder II. It is highly likely the Cardinal had also died by this point then.

Cardinal Blackadder is definitely the father of a certain Lord Edmund Blackadder. If his son has the Blackadder lordship, it would be reasonable to suppose that he is either the Edmund Blackadder of Blackadder II, or his father from whom he inherited the title.

If Cardinal Blackadder is the father of Edmund of Blackadder II, then he is the grandson of Prince Edmund. However, this would seem almost impossible, because to have been a Cardinal in 1509 he would have been too old to be the grandson of Prince Edmund who died in 1498.

This leads to the conclusion that he is the son of The Black Adder, and therefore the grandfather of Edmund Blackadder of Blackadder II.